Best Battery Maintainers: Keep Your Car Battery In Prime Condition

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If your battery ever dies, your first reaction is probably to replace it immediately. Unlike modern lithium-ion batteries, a car battery isn't something you can simply plug into the wall to recharge. With the right battery maintainer, however, it's possible to keep its charge up without having to worry about it going dead or to bring it back to life.

One of the best single-bank battery maintainers and chargers available for anyone wanting a simple setup.

Pros

Pros

Very simple to use. Tender does most of the work in terms of protecting the battery from overcharge or damage.

Cons

Cons

Alligator clips are small and awkward to fit over larger battery posts. No level charge indicator.

Why Buy a Battery Maintainer

Keep car batteries charged. The lifespan of most car batteries is fairly straightforward: The charge slowly decreases until there is no juice left. A battery maintainer makes it easy to keep the battery "topped" every now and then so you can extend the battery life. Some can also tackle other vehicle batteries like a motorcycle battery.

Store batteries when not in use. All batteries lose their charge over time, even when they aren't in use. A maintainer is a good way to store batteries long term. The maintainer will keep the battery charged without the risk of overcharging or damaging it.

Restore old batteries. Not all battery maintainers can bring a battery back from the dead, but some maintainer and charger combos can alternate modes to for the type of battery charging required to bring old lead-acid batteries back to a full charge.

Types of Battery Maintainers

Single-Bank Tender

This is the most basic and common type of battery maintainer. Meant for a single battery, this type of tender tends to be less expensive than other options and can offer some intelligent charging features at the same time.

Multi-Bank Tender

When you have more than one battery you want to maintain, this is the type of tender to choose. Coming in different bank amounts like two, four, or 10 banks, these tenders can work with multiple batteries at the same time, as long as you have long enough cables.

Hybrid Tender

Some manufacturers like to pack more utility in their battery tending options. As a result, hybrid tenders tend to offer different charging modes so it can actually charge a dead or near-dead battery and keep it full over a long period of time.

Top Brands of Battery Maintainers

NOCO

Started in 1914, NOCO is a premium manufacturer of battery accessories like chargers, tenders, jump starters and solar panels. The company focuses on designing battery products that are small in size but powerful enough to handle larger batteries. For automotive use, the NOCO Genius is a stellar tender that makes it easy to bring a dead battery back to life.

Battery Tender

There shouldn't be any confusion over what Deltran Battery Tender is all about. Since 1965, the company has offered a large line of batteries and charging accessories for automotive, marine, and other uses. The company's battery maintainers, like the Battery Tender Plus, offer a lot of options for maintaining the different vehicle and battery types and numbers.

Battery Maintainer Pricing

$100 and under: Budget tenders tend to be either charging and maintainer combos meant for portable use or single-bank tenders that pack some useful smart features. Either way, this is a good range to consider if you simply want a basic maintainer.

$100-$200: This range is full of advanced single-bank tenders mixed with a few multi-bank options. Most multi-bank tenders here are generally limited to four or five batteries at a time.

$200 and above: The upper range of battery maintainers is also fairly limited to professional-grade maintainers with large battery bank capacities. Tenders up to 10 banks, for example, are common in this range. You'll also find the most user-friendly options here.

Key Features

Amperage

Amperage is the amount of current that can flow from the device to a battery. Higher amps tend to mean faster charging times, but this isn't always desirable for a battery maintainer. Since most maintainers are meant for long-term use, low-amp models use less energy to keep batteries full. If you want a quick recharge time, however, high amps are beneficial.

Charging Mode

Many high-amp battery maintainers come with different charging modes for different scenarios. Tenders that can actually charge a dead battery will often have a "fast charge" mode where the full amp limit is used to deliver a lot of juice in a short amount of time. "Maintenance" modes are common for keeping batteries charged over a long period of time.

Safety Features

Charging any kind of battery can be dangerous, especially if the charger or maintainer doesn't have a few safety features to keep the power controlled. Common safety features include spark-proof clamps, reverse polarity protection/warnings, auto volt and amp limits to prevent overcharging, and short circuit protection. Smart battery maintainers tend to make the most use of these features automatically so you don't have to worry about safe charging; it's just plug-and-play operation.

Other Considerations

Smart Features: Charging a battery normally isn't as simple as plugging it in and waiting for it to get full; at least, now without some help. Smart features that monitor the battery's charge are important for preventing overcharging. This is what makes most tenders different from trickle chargers that deliver a constant charge. Maintainers can shut off the juice when necessary, while trickle chargers keep working no matter what.

Exterior Protection: A small amount of waterproof protection goes a long way for most battery maintainers. Since you will likely keep the tender out in the garage, potentially exposed to moisture and the elements, a rugged exterior is a good investment. This will prevent the tender from getting damaged, which increases overall safety as well.

Best Battery Maintainers Reviews & Recommendations 2019

The Battery Tender Management System offers bulk battery maintenance capabilities that are meant for handling several batteries at once. The benefit of this multi-battery approach should be noticeable to multivehicle owners or professional mechanics: You can tend to more vehicles at once. Within the company's battery management system, there are several models that increase the size of the bank, from 2-10 batteries at a time.

The tender offers a lot of high-end features for its high-end price tag. For example, it does a good job of "reading" the battery to determine the right charge to avoid overcharging or damaging the battery. The tender is compatible with many different types of 12-volt batteries and makes a great maintaining solution for marine and RV batteries as well.

The larger bank tending options may seem like overkill for the average vehicle owner, but anything above the four-bank batteries will be perfect for professional use or multi-vehicle owners. Unfortunately, these models come with short leads, making it difficult to reach multiple batteries sitting inside multiple vehicles at the same time without parking the vehicles just right so everything fits within reach of the tender.

NOCO's Genius battery charger and maintainer combo come in at a budget price with some advanced, smart features to protect the battery, your vehicle, and, possibly, yourself. As a result, this is a good tender option to consider if you want something that takes away the danger and challenge of bringing an automotive battery back from the dead. Its portable size also makes it a great option to bring around on trips.

The tender series comes with several options ranging from 0.75 to 26 amps, with a four-bank 4.4-amp tender thrown into the mix for good measure. Great for beginners, the instructions are easy to follow and accurately reflect the basic charging and tending process of the device. The design of the box is strong, sturdy, and can be mounted permanently to a solid surface. While working, the low-amp models do a good job of staying cool on the surface.

As a budget-focused, hybrid automatic battery charger and maintainer, the device has a few shortcomings compared to dedicated tenders. Visually, all you get is some indicator lights; its lack of a display means it can't show voltage. The crocodile clips have a slightly awkward shape where the plastic can interfere or hang up on the battery itself.

The Battery Tender Plus, like the Battery Tender Junior, is about as good as it gets when it comes to a single-bank smart battery charger and tender. Packing in a lot of smart features into a relatively small, compact body, the Plus is a 1.25-amp battery charger and maintainer that does a lot of the heavy lifting in terms of finding the appropriate charge for a battery based on its type and power level. The device can also automatically switch between charging and maintenance modes for long-term battery support.

Easy operation is this tenders biggest highlight, especially for anyone who doesn't have much experience with resurrecting dead batteries. The tender comes simple-to-use cables that clamp on just like jumper cables. Beyond the use, the battery maintainer does a good job of keeping the heat down and charging most batteries within a 24-hour period.

On the negative side, the included alligator clips are on the small side, making it difficult to clamp them onto larger posts. The LED indicators can also be confusing since there is only a red LED for charging and a green LED for the completed status. An actual level indicator would be better to get an accurate sense of where the tender is during charging operations.

Tips

Take some time to consider the output of a potential battery maintainer. Higher amounts of amps are good for fast charging but will use more energy, so low-amp outputs are good to consider for energy saving gains.

Safety always needs to be paramount when using any kind of charger. Read the instructions ahead of time to know exactly how to use the tender before connecting a battery.

A good battery maintainer should be easy to use. The most simple process is a simple plug-and-play setup: connect the clamps to the terminals, turn on the tender, and let it do its work.

Look for a tender with an automatic charging feature if you need one for battery storage. This feature will allow the tender to keep the battery periodically charged without requiring intervention from you.

FAQ

Q. How do I know if my battery is dead?

A. The most obvious sign a lead-acid car battery is dead is when the car's engine fails to start. It may crank up but never reach sustained operation. The car's electronics may also fail to work properly, even when the engine is off. It's helpful to keep the battery charged well before this point, however.

Q. How long does it take to charge a battery?

A. This depends on the battery's capacity (amp hours) and the device's current (amps). You can divide the capacity by the current to get the number of hours it will likely take to charge it to full.

Q. Why is under or overcharging a battery an issue?

A. Unregulated, continuous or trickle charging can eventually deliver more charge than a battery can handle. This presents the possibility of damaging the battery, the charger and maintainer, and anything around them. Smart chargers and maintainers with float modes and automatic charging, on the other hand, can shut off when the battery reaches its maximum capacity so the danger is minimized.